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    <title>Document</title>
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    * {
        margin: 0;
        padding: 0;
        /* 全局解决内边距撑大盒子的问题 */
        box-sizing: border-box;
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    li {
        list-style: none;
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    <h1>
        标题
    </h1>
    <p>ppppppppppppp</p>
    <ul>
        <li>lililili</li>
    </ul>
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